This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Our primary specific aim is to validate the CASI-DH and the DietDay against recovery and concentration biomarkers as follows: 1) To examine the validity of the CASI-DH and DietDay for assessing intakes of total energy in comparison to the total energy expenditure assessed through the doubly labeled water technique, a gold standard energy intake validation biomarker. 2) To examine the validity of the CASI-DH and DietDay for assessing intakes of total protein in comparison to PABA (para-amino benzoic acid) validated 24-hour sample measurements of urinary nitrogen for protein, a well-established protein intake biomarker and for dietary potassium using the same biological sample. 3) To examine the validity of the CASI-DH for assessing intakes of fruits and vegetables, in comparison to blood levels of carotenoids.